예제 #1
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파일: sdss.py 프로젝트: lyczek/tractor
def _check_sdss_files(sdss, run, camcol, field, bandname, filetypes,
                      retrieve=True, tryopen=False):
    from astrometry.sdss import band_index

    bandnum = band_index(bandname)
    for filetype in filetypes:
        fn = sdss.getPath(filetype, run, camcol, field, bandname)
        print('Looking for file', fn)
        exists = os.path.exists(fn)
        retrieveKwargs = {}
        if exists and tryopen:
            import pyfits
            # This doesn't catch *all* types of errors you can imagine...
            try:
                T = pyfits.open(fn)
            except:
                print('Failed to open file', fn, 'as FITS file: maybe corrupt.')
                exists = False
                retrieveKwargs.update(skipExisting=False)
                
        if (not exists) and retrieve:
            print('Retrieving', fn)
            res = sdss.retrieve(filetype, run, camcol, field, bandnum,
                                **retrieveKwargs)
            if res is False:
                raise RuntimeError('No such file on SDSS DAS: %s, ' % filetype +
                                   'rcfb %i/%i/%i/%s' %
                                   (run, camcol, field, bandname))
        elif not exists:
            raise os.OSError('no such file: "%s"' % fn)
예제 #2
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    def __init__(self, tsfield, bandname):
        from astrometry.sdss import band_index

        self.bandname = bandname
        self.band = band_index(bandname)

        #self.tsfield = tsfield
        band = self.band
        self.exptime = tsfield.exptime
        self.aa = tsfield.aa[band]
        self.kk = tsfield.kk[band]
        self.airmass = tsfield.airmass[band]

        super(SdssMagsPhotoCal, self).__init__()
예제 #3
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파일: sdss.py 프로젝트: lyczek/tractor
    def __init__(self, tsfield, bandname):
        from astrometry.sdss import band_index
        
        self.bandname = bandname
        self.band = band_index(bandname)

        #self.tsfield = tsfield
        band = self.band
        self.exptime = tsfield.exptime
        self.aa = tsfield.aa[band]
        self.kk = tsfield.kk[band]
        self.airmass = tsfield.airmass[band]

        super(SdssMagsPhotoCal,self).__init__()
예제 #4
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def sdss_coadd(targetwcs, bands):
    from astrometry.sdss import DR9, band_index
    from astrometry.sdss import AsTransWrapper

    #sdss = DR9(basedir=photoobjdir)
    #sdss.useLocalTree()
    sdss = DR9(basedir='tmp')
    sdss.saveUnzippedFiles('tmp')

    #wfn = sdss.filenames.get('window_flist', None)
    wfn = os.path.join(os.environ.get('PHOTO_RESOLVE', ''),
                       'window_flist.fits')

    from astrometry.sdss.fields import radec_to_sdss_rcf

    ra, dec = targetwcs.radec_center()
    rad = targetwcs.radius()
    rad = rad + np.hypot(10., 14.) / 2. / 60.
    print('Searching for run,camcol,fields with radius', rad, 'deg')
    RCF = radec_to_sdss_rcf(ra, dec, radius=rad * 60., tablefn=wfn)
    print('Found %i fields possibly in range' % len(RCF))

    H, W = targetwcs.shape
    sdsscoimgs = [np.zeros((H, W), np.float32) for band in bands]
    sdsscons = [np.zeros((H, W), np.float32) for band in bands]
    for run, camcol, field, r, d in RCF:
        for iband, band in enumerate(bands):
            bandnum = band_index(band)
            sdss.retrieve('frame', run, camcol, field, band)
            frame = sdss.readFrame(run, camcol, field, bandnum)
            print('Got frame', frame)
            h, w = frame.getImageShape()
            simg = frame.getImage()
            wcs = AsTransWrapper(frame.astrans, w, h, 0.5, 0.5)
            try:
                Yo, Xo, Yi, Xi, nil = resample_with_wcs(targetwcs, wcs)
            except OverlapError:
                continue
            sdsscoimgs[iband][Yo, Xo] += simg[Yi, Xi]
            sdsscons[iband][Yo, Xo] += 1
    for co, n in zip(sdsscoimgs, sdsscons):
        co /= np.maximum(1e-6, n)

    return sdsscoimgs, sdsscons
예제 #5
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def sdss_coadd(targetwcs, bands):
    from astrometry.sdss import DR9, band_index
    from astrometry.sdss import AsTransWrapper

    #sdss = DR9(basedir=photoobjdir)
    #sdss.useLocalTree()
    sdss = DR9(basedir='tmp')
    sdss.saveUnzippedFiles('tmp')

    #wfn = sdss.filenames.get('window_flist', None)
    wfn = os.path.join(os.environ.get('PHOTO_RESOLVE',''), 'window_flist.fits')

    from astrometry.sdss.fields import radec_to_sdss_rcf
    
    ra,dec = targetwcs.radec_center()
    rad = targetwcs.radius()
    rad = rad + np.hypot(10.,14.)/2./60.
    print 'Searching for run,camcol,fields with radius', rad, 'deg'
    RCF = radec_to_sdss_rcf(ra, dec, radius=rad*60., tablefn=wfn)
    print 'Found %i fields possibly in range' % len(RCF)

    H,W = targetwcs.shape
    sdsscoimgs = [np.zeros((H,W),np.float32) for band in bands]
    sdsscons   = [np.zeros((H,W),np.float32) for band in bands]
    for run,camcol,field,r,d in RCF:
        for iband,band in enumerate(bands):
            bandnum = band_index(band)
            sdss.retrieve('frame', run, camcol, field, band)
            frame = sdss.readFrame(run, camcol, field, bandnum)
            print 'Got frame', frame
            h,w = frame.getImageShape()
            simg = frame.getImage()
            wcs = AsTransWrapper(frame.astrans, w, h, 0.5, 0.5)
            try:
                Yo,Xo,Yi,Xi,nil = resample_with_wcs(targetwcs, wcs, [], 3)
            except OverlapError:
                continue
            sdsscoimgs[iband][Yo,Xo] += simg[Yi,Xi]
            sdsscons  [iband][Yo,Xo] += 1
    for co,n in zip(sdsscoimgs, sdsscons):
        co /= np.maximum(1e-6, n)

    return sdsscoimgs, sdsscons
예제 #6
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def _check_sdss_files(sdss,
                      run,
                      camcol,
                      field,
                      bandname,
                      filetypes,
                      retrieve=True,
                      tryopen=False):
    from astrometry.sdss import band_index

    bandnum = band_index(bandname)
    for filetype in filetypes:
        fn = sdss.getPath(filetype, run, camcol, field, bandname)
        print('Looking for file', fn)
        exists = os.path.exists(fn)
        retrieveKwargs = {}
        if exists and tryopen:
            # This doesn't catch *all* types of errors you can imagine...
            cmd = 'fitsverify -q %s' % fn
            try:
                print('Running:', cmd)
                rtn = os.system(cmd)
                print('rtn:', rtn)
                if rtn != 0:
                    exists = False
            except:
                print('Failed to fitsverify', fn, ': maybe corrupt.')
                exists = False
            if not exists:
                retrieveKwargs.update(skipExisting=False)

        if (not exists) and retrieve:
            print('Retrieving', fn)
            res = sdss.retrieve(filetype, run, camcol, field, bandnum,
                                **retrieveKwargs)
            if res is False:
                raise RuntimeError('No such file on SDSS DAS: %s, ' %
                                   filetype + 'rcfb %i/%i/%i/%s' %
                                   (run, camcol, field, bandname))
        elif not exists:
            raise OSError('no such file: "%s", or failed to verify' % fn)
예제 #7
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def _check_sdss_files(sdss,
                      run,
                      camcol,
                      field,
                      bandname,
                      filetypes,
                      retrieve=True,
                      tryopen=False):
    from astrometry.sdss import band_index

    bandnum = band_index(bandname)
    for filetype in filetypes:
        fn = sdss.getPath(filetype, run, camcol, field, bandname)
        print('Looking for file', fn)
        exists = os.path.exists(fn)
        retrieveKwargs = {}
        if exists and tryopen:
            import pyfits
            # This doesn't catch *all* types of errors you can imagine...
            try:
                T = pyfits.open(fn)
            except:
                print('Failed to open file', fn,
                      'as FITS file: maybe corrupt.')
                exists = False
                retrieveKwargs.update(skipExisting=False)

        if (not exists) and retrieve:
            print('Retrieving', fn)
            res = sdss.retrieve(filetype, run, camcol, field, bandnum,
                                **retrieveKwargs)
            if res is False:
                raise RuntimeError('No such file on SDSS DAS: %s, ' %
                                   filetype + 'rcfb %i/%i/%i/%s' %
                                   (run, camcol, field, bandname))
        elif not exists:
            raise os.OSError('no such file: "%s"' % fn)
예제 #8
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def get_tractor_image_dr7(run, camcol, field, bandname,
                          sdssobj=None, release='DR7',
                          retrieve=True, curl=False,
                          psf='kl-gm', useMags=False,
                          roi=None,
                          roiradecsize=None,
                          roiradecbox=None,
                          nanomaggies=False,
                          savepsfimg=None, zrange=[-3, 10]):
    '''
    Creates a tractor.Image given an SDSS field identifier.

    If not None, roi = (x0, x1, y0, y1) defines a region-of-interest
    in the image, in zero-indexed pixel coordinates.  x1,y1 are
    NON-inclusive; roi=(0,100,0,100) will yield a 100 x 100 image.

    psf can be:
      "dg" for double-Gaussian
      "kl-gm" for SDSS KL-decomposition approximated as a Gaussian mixture

    "roiradecsize" = (ra, dec, half-size in pixels) indicates that you
    want to grab a ROI around the given RA,Dec.

    Returns:
      (tractor.Image, dict)

    dict contains useful details like:
      'sky'
      'skysig'
    '''
    from astrometry.sdss import DR7, band_index

    if sdssobj is None:
        # Ugly
        if release != 'DR7':
            raise RuntimeError('We only support DR7 currently')
        sdss = DR7(curl=curl)
    else:
        sdss = sdssobj

    valid_psf = ['dg', 'kl-gm']
    if psf not in valid_psf:
        raise RuntimeError('PSF must be in ' + str(valid_psf))
    # FIXME
    rerun = 0

    bandnum = band_index(bandname)

    _check_sdss_files(sdss, run, camcol, field, bandname,
                      ['fpC', 'tsField', 'psField', 'fpM'],
                      retrieve=retrieve)
    fpC = sdss.readFpC(run, camcol, field, bandname)
    hdr = fpC.getHeader()
    fpC = fpC.getImage()
    fpC = fpC.astype(np.float32) - sdss.softbias
    image = fpC
    (H, W) = image.shape

    info = dict()
    tai = hdr.get('TAI')
    stripe = hdr.get('STRIPE')
    strip = hdr.get('STRIP')
    obj = hdr.get('OBJECT')
    info.update(tai=tai, stripe=stripe, strip=strip, object=obj, hdr=hdr)

    tsf = sdss.readTsField(run, camcol, field, rerun)
    astrans = tsf.getAsTrans(bandnum)
    wcs = SdssWcs(astrans)
    #print('Created SDSS Wcs:', wcs)

    X = interpret_roi(wcs, (H, W), roi=roi, roiradecsize=roiradecsize,
                      roiradecbox=roiradecbox)
    if X is None:
        return None, None
    roi, hasroi = X
    info.update(roi=roi)
    x0, x1, y0, y1 = roi

    # Mysterious half-pixel shift.  asTrans pixel coordinates?
    wcs.setX0Y0(x0 + 0.5, y0 + 0.5)

    if nanomaggies:
        zp = tsf.get_zeropoint(bandnum)
        photocal = LinearPhotoCal(NanoMaggies.zeropointToScale(zp),
                                  band=bandname)
    elif useMags:
        photocal = SdssMagsPhotoCal(tsf, bandname)
    else:
        photocal = SdssFluxPhotoCal()

    psfield = sdss.readPsField(run, camcol, field)
    sky = psfield.getSky(bandnum)
    skysig = sqrt(sky)
    skyobj = ConstantSky(sky)
    zr = sky + np.array(zrange) * skysig
    info.update(sky=sky, skysig=skysig, zr=zr)

    fpM = sdss.readFpM(run, camcol, field, bandname)
    gain = psfield.getGain(bandnum)
    darkvar = psfield.getDarkVariance(bandnum)
    skyerr = psfield.getSkyErr(bandnum)
    invvar = sdss.getInvvar(fpC, fpM, gain, darkvar, sky, skyerr)

    dgpsf = psfield.getDoubleGaussian(bandnum, normalize=True)
    info.update(dgpsf=dgpsf)

    if roi is not None:
        roislice = (slice(y0, y1), slice(x0, x1))
        image = image[roislice].copy()
        invvar = invvar[roislice].copy()

    if psf == 'kl-gm':
        from emfit import em_fit_2d
        from fitpsf import em_init_params

        # Create Gaussian mixture model PSF approximation.
        H, W = image.shape
        klpsf = psfield.getPsfAtPoints(bandnum, x0 + W / 2, y0 + H / 2)
        S = klpsf.shape[0]
        # number of Gaussian components
        K = 3
        w, mu, sig = em_init_params(K, None, None, None)
        II = klpsf.copy()
        II /= II.sum()
        # HIDEOUS HACK
        II = np.maximum(II, 0)
        #print('Multi-Gaussian PSF fit...')
        xm, ym = -(S / 2), -(S / 2)
        if savepsfimg is not None:
            plt.clf()
            plt.imshow(II, interpolation='nearest', origin='lower')
            plt.title('PSF image to fit with EM')
            plt.savefig(savepsfimg)
        res = em_fit_2d(II, xm, ym, w, mu, sig)
        print('em_fit_2d result:', res)
        if res == 0:
            # print('w,mu,sig', w,mu,sig)
            mypsf = GaussianMixturePSF(w, mu, sig)
            mypsf.computeRadius()
        else:
            # Failed!  Return 'dg' model instead?
            print('PSF model fit', psf, 'failed!  Returning DG model instead')
            psf = 'dg'
    if psf == 'dg':
        print('Creating double-Gaussian PSF approximation')
        (a, s1, b, s2) = dgpsf
        mypsf = NCircularGaussianPSF([s1, s2], [a, b])

    timg = Image(data=image, invvar=invvar, psf=mypsf, wcs=wcs,
                 sky=skyobj, photocal=photocal,
                 name=('SDSS (r/c/f/b=%i/%i/%i/%s)' %
                       (run, camcol, field, bandname)))
    timg.zr = zr
    return timg, info
예제 #9
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def _get_tractor_image_dr8(run,
                           camcol,
                           field,
                           bandname,
                           sdss=None,
                           roi=None,
                           psf='kl-gm',
                           roiradecsize=None,
                           roiradecbox=None,
                           savepsfimg=None,
                           curl=False,
                           nanomaggies=False,
                           zrange=[-3, 10],
                           invvarIgnoresSourceFlux=False,
                           invvarAtCenter=False,
                           invvarAtCenterImage=False,
                           retrieve=True,
                           imargs={}):
    from astrometry.sdss import band_index

    origpsf = psf
    if psf.startswith('bright-'):
        psf = psf[7:]
        brightpsf = True
        print('Setting bright PSF handling')
    else:
        brightpsf = False

    valid_psf = ['dg', 'kl-gm', 'kl-pix']
    if psf not in valid_psf:
        raise RuntimeError('PSF must be in ' + str(valid_psf))

    if sdss is None:
        from astrometry.sdss import DR8
        sdss = DR8(curl=curl)

    bandnum = band_index(bandname)

    if retrieve:
        for ft in ['psField', 'fpM']:
            fn = sdss.retrieve(ft, run, camcol, field, bandname)
        fn = sdss.retrieve('frame', run, camcol, field, bandname)
    else:
        fn = sdss.getPath('frame', run, camcol, field, bandname)

    # http://data.sdss3.org/datamodel/files/BOSS_PHOTOOBJ/frames/RERUN/RUN/CAMCOL/frame.html
    frame = sdss.readFrame(run, camcol, field, bandname, filename=fn)
    H, W = frame.getImageShape()
    info = dict()
    hdr = frame.getHeader()
    tai = hdr.get('TAI')
    stripe = hdr.get('STRIPE')
    strip = hdr.get('STRIP')
    obj = hdr.get('OBJECT')
    info.update(tai=tai, stripe=stripe, strip=strip, object=obj, hdr=hdr)

    astrans = frame.getAsTrans()
    wcs = SdssWcs(astrans)
    #print('Created SDSS Wcs:', wcs)
    #print('(x,y) = 1,1 -> RA,Dec', wcs.pixelToPosition(1,1))

    X = interpret_roi(wcs, (H, W),
                      roi=roi,
                      roiradecsize=roiradecsize,
                      roiradecbox=roiradecbox)
    if X is None:
        return None, None
    roi, hasroi = X
    info.update(roi=roi)
    x0, x1, y0, y1 = roi

    # Half-pixel shift for asTrans pixel coordinates.
    wcs.setX0Y0(x0 + 0.5, y0 + 0.5)

    if nanomaggies:
        photocal = LinearPhotoCal(1., band=bandname)
    else:
        photocal = MagsPhotoCal(bandname, 22.5)

    sky = 0.
    skyobj = ConstantSky(sky)

    calibvec = frame.getCalibVec()

    invvarAtCenter = invvarAtCenter or invvarAtCenterImage

    psfield = sdss.readPsField(run, camcol, field)
    iva = dict(ignoreSourceFlux=invvarIgnoresSourceFlux)
    if invvarAtCenter:
        if hasroi:
            iva.update(constantSkyAt=(int((x0 + x1) / 2.),
                                      int((y0 + y1) / 2.)))
        else:
            iva.update(constantSkyAt=(int(W / 2.), int(H / 2.)))
    invvar = frame.getInvvar(psfield, bandnum, **iva)
    invvar = invvar.astype(np.float32)
    if not invvarAtCenter:
        assert (invvar.shape == (H, W))

    # Could get this from photoField instead
    # http://data.sdss3.org/datamodel/files/BOSS_PHOTOOBJ/RERUN/RUN/photoField.html
    gain = psfield.getGain(bandnum)
    darkvar = psfield.getDarkVariance(bandnum)

    meansky = np.mean(frame.sky)
    meancalib = np.mean(calibvec)
    skysig = sqrt((meansky / gain) + darkvar) * meancalib

    info.update(sky=sky, skysig=skysig)
    zr = np.array(zrange) * skysig + sky
    info.update(zr=zr)

    # http://data.sdss3.org/datamodel/files/PHOTO_REDUX/RERUN/RUN/objcs/CAMCOL/fpM.html
    fpM = sdss.readFpM(run, camcol, field, bandname)

    if not hasroi:
        image = frame.getImage()

    else:
        roislice = (slice(y0, y1), slice(x0, x1))
        image = frame.getImageSlice(roislice).astype(np.float32)
        if invvarAtCenterImage:
            invvar = invvar + np.zeros(image.shape, np.float32)
        elif invvarAtCenter:
            pass
        else:
            invvar = invvar[roislice].copy()
        H, W = image.shape

    if (not invvarAtCenter) or invvarAtCenterImage:
        for plane in ['INTERP', 'SATUR', 'CR', 'GHOST']:
            fpM.setMaskedPixels(plane, invvar, 0, roi=roi)

    dgpsf = psfield.getDoubleGaussian(bandnum, normalize=True)
    info.update(dgpsf=dgpsf)

    if psf == 'kl-pix':
        # Pixelized KL-PSF
        klpsf = psfield.getPsfAtPoints(bandnum, x0 + W / 2, y0 + H / 2)
        # Trim symmetric zeros
        sh, sw = klpsf.shape
        while True:
            if (np.all(klpsf[0, :] == 0.) and np.all(klpsf[:, 0] == 0.)
                    and np.all(klpsf[-1, :] == 0.)
                    and np.all(klpsf[:, -1] == 0.)):
                klpsf = klpsf[1:-1, 1:-1]
            else:
                break
        mypsf = PixelizedPSF(klpsf)

    elif psf == 'kl-gm':
        from tractor.emfit import em_fit_2d
        from tractor.fitpsf import em_init_params

        # Create Gaussian mixture model PSF approximation.
        klpsf = psfield.getPsfAtPoints(bandnum, x0 + W / 2, y0 + H / 2)
        S = klpsf.shape[0]
        # number of Gaussian components
        K = 3
        w, mu, sig = em_init_params(K, None, None, None)
        II = klpsf.copy()
        II /= II.sum()
        # HIDEOUS HACK
        II = np.maximum(II, 0)
        #print('Multi-Gaussian PSF fit...')
        xm, ym = -(S // 2), -(S // 2)
        if savepsfimg is not None:
            plt.clf()
            plt.imshow(II, interpolation='nearest', origin='lower')
            plt.title('PSF image to fit with EM')
            plt.savefig(savepsfimg)
        res = em_fit_2d(II, xm, ym, w, mu, sig)
        #print('em_fit_2d result:', res)
        if res == 0:
            # print('w,mu,sig', w,mu,sig)
            mypsf = GaussianMixturePSF(w, mu, sig)
            mypsf.computeRadius()
        else:
            # Failed!  Return 'dg' model instead?
            print('PSF model fit', psf, 'failed!  Returning DG model instead')
            psf = 'dg'
    if psf == 'dg':
        print('Creating double-Gaussian PSF approximation')
        (a, s1, b, s2) = dgpsf
        mypsf = NCircularGaussianPSF([s1, s2], [a, b])

    if brightpsf:
        print('Wrapping PSF in SdssBrightPSF')
        (a1, s1, a2, s2, a3, sigmap, beta) = psfield.getPowerLaw(bandnum)
        mypsf = SdssBrightPSF(mypsf, a1, s1, a2, s2, a3, sigmap, beta)
        print('PSF:', mypsf)

    timg = Image(data=image,
                 invvar=invvar,
                 psf=mypsf,
                 wcs=wcs,
                 sky=skyobj,
                 photocal=photocal,
                 name=('SDSS (r/c/f/b=%i/%i/%i/%s)' %
                       (run, camcol, field, bandname)),
                 time=TAITime(tai),
                 **imargs)
    timg.zr = zr
    return timg, info
예제 #10
0
def _get_sources(run,
                 camcol,
                 field,
                 bandname='r',
                 sdss=None,
                 release='DR7',
                 objs=None,
                 retrieve=True,
                 checkFiles=True,
                 curl=False,
                 roi=None,
                 radecroi=None,
                 radecrad=None,
                 bands=None,
                 badmag=25,
                 nanomaggies=False,
                 getobjs=False,
                 getsourceobjs=False,
                 getobjinds=False,
                 extrabands=None,
                 fixedComposites=False,
                 forcePointSources=False,
                 useObjcType=False,
                 objCuts=True,
                 classmap={},
                 ellipse=GalaxyShape,
                 cutToPrimary=False):
    '''
    If set,

    radecrad = (ra,dec,rad)

    returns sources within "rad" degrees of the given RA,Dec (in degrees)
    center.

    WARNING, this method alters the "objs" argument, if given.
    Consider calling objs.copy() before calling.

    -"bandname" is the SDSS band used to cut on position, select
     star/gal/exp/dev, and set galaxy shapes.

    -"bands" are the bands to include in the returned Source objects;
     they will be initialized from the SDSS bands.

    -"extrabands" are also included in the returned Source objects;
     they will be initialized to the SDSS flux for either the first of
     "bands", if given, or "bandname".
    '''
    from astrometry.sdss import (DR7, DR8, DR9, band_names, band_index,
                                 photo_flags1_map)

    #   brightPointSourceThreshold=0.):

    if sdss is None:
        dr = dict(DR7=DR7, DR8=DR8, DR9=DR9)[release]
        sdss = dr(curl=curl)
    drnum = sdss.getDRNumber()
    isdr7 = (drnum == 7)

    if bands is None:
        bands = band_names()
    bandnum = band_index(bandname)

    bandnums = np.array([band_index(b) for b in bands])
    bandnames = bands

    if extrabands is None:
        extrabands = []

    if objs is None:
        from astrometry.util.fits import fits_table
        if isdr7:
            # FIXME
            rerun = 0
            if checkFiles:
                _check_sdss_files(sdss,
                                  run,
                                  camcol,
                                  field,
                                  bandnum, ['tsObj', 'tsField'],
                                  retrieve=retrieve,
                                  tryopen=True)
            tsf = sdss.readTsField(run, camcol, field, rerun)
            objfn = sdss.getPath('tsObj',
                                 run,
                                 camcol,
                                 field,
                                 bandname,
                                 rerun=rerun)
        else:
            if checkFiles:
                _check_sdss_files(sdss,
                                  run,
                                  camcol,
                                  field,
                                  bandnum, ['photoObj'],
                                  retrieve=retrieve,
                                  tryopen=True)
            objfn = sdss.getPath('photoObj', run, camcol, field)

        objs = fits_table(objfn)
        if objs is None:
            print('No sources in SDSS file', objfn)
            return []

    objs.index = np.arange(len(objs))
    if getobjs:
        allobjs = objs.copy()

    if roi is not None:
        x0, x1, y0, y1 = roi
        # FIXME -- we keep only the sources whose centers are within
        # the ROI box.  Should instead do some ellipse-overlaps
        # geometry.
        x = objs.colc[:, bandnum]
        y = objs.rowc[:, bandnum]
        objs.cut((x >= x0) * (x < x1) * (y >= y0) * (y < y1))

    if radecroi is not None:
        r0, r1, d0, d1 = radecroi
        objs.cut((objs.ra >= r0) * (objs.ra <= r1) * (objs.dec >= d0) *
                 (objs.dec <= d1))

    if radecrad is not None:
        from astrometry.libkd.spherematch import match_radec
        (ra, dec, rad) = radecrad
        I, J, d = match_radec(ra, dec, objs.ra, objs.dec, rad)
        objs.cut(J)
        del I
        del d

    if objCuts:
        # Only deblended children;
        # No BRIGHT sources
        bright = photo_flags1_map.get('BRIGHT')
        objs.cut((objs.nchild == 0) * ((objs.objc_flags & bright) == 0))

    if cutToPrimary:
        objs.cut((objs.resolve_status & 256) > 0)

    if len(objs) == 0:
        sources = []
        if not (getobjs or getobjinds or getsourceobjs):
            return sources
        rtn = [sources]
        if getobjs:
            rtn.append(None)
        if getobjinds:
            rtn.append(None)
        if getsourceobjs:
            rtn.append(None)
        return rtn

    if isdr7:
        objs.rename('phi_dev', 'phi_dev_deg')
        objs.rename('phi_exp', 'phi_exp_deg')
        objs.rename('r_dev', 'theta_dev')
        objs.rename('r_exp', 'theta_exp')

    # SDSS and Tractor have different opinions on which way this rotation goes
    objs.phi_dev_deg *= -1.
    objs.phi_exp_deg *= -1.

    # MAGIC -- minimum size of galaxy.
    objs.theta_dev = np.maximum(objs.theta_dev, 1. / 30.)
    objs.theta_exp = np.maximum(objs.theta_exp, 1. / 30.)

    if forcePointSources:
        Lstar = np.ones(len(objs), float)
        Lgal = np.zeros(len(objs), float)
        Ldev = Lexp = Lgal
    else:
        if useObjcType:
            objs.cut(np.logical_or(objs.objc_type == 6, objs.objc_type == 3))
            Lstar = (objs.objc_type == 6)
            Lgal = (objs.objc_type == 3)
        else:
            Lstar = (objs.prob_psf[:, bandnum] == 1) * 1.0
            Lgal = (objs.prob_psf[:, bandnum] == 0) * 1.0

        if isdr7:
            fracdev = objs.fracpsf[:, bandnum]
        else:
            fracdev = objs.fracdev[:, bandnum]
        Ldev = Lgal * fracdev
        Lexp = Lgal * (1. - fracdev)

    if isdr7:
        from .sdss_dr7 import _dr7_getBrightness
        if nanomaggies:
            raise RuntimeError('Nanomaggies not supported for DR7 (yet)')

        def lup2bright(lups):
            counts = [
                tsf.luptitude_to_counts(lup, j) for j, lup in enumerate(lups)
            ]
            counts = np.array(counts)
            bright = _dr7_getBrightness(counts, tsf, bandnames, extrabands)
            return bright

        flux2bright = lup2bright
        starflux = objs.psfcounts
        compflux = objs.counts_model
        devflux = objs.counts_dev
        expflux = objs.counts_exp

        def comp2bright(lups, Ldev, Lexp):
            counts = [
                tsf.luptitude_to_counts(lup, j) for j, lup in enumerate(lups)
            ]
            counts = np.array(counts)
            dcounts = counts * Ldev
            ecounts = counts * Lexp
            dbright = _dr7_getBrightness(dcounts, tsf, bands, extrabands)
            ebright = _dr7_getBrightness(ecounts, tsf, bands, extrabands)
            return dbright, ebright
    else:

        def nmgy2bright(flux):
            if len(bandnums):
                flux = flux[bandnums]
            else:
                flux = flux[np.array([bandnum])]
            bb = bandnames + extrabands
            if nanomaggies:
                if len(extrabands):
                    if len(bandnums) == 0:
                        # Only "extrabands", no SDSS bands.
                        flux = np.zeros(len(extrabands)) + flux[0]
                    else:
                        flux = np.append(flux, np.zeros(len(extrabands)))
                bright = NanoMaggies(order=bb, **dict(zip(bb, flux)))
            else:
                I = (flux > 0)
                mag = np.zeros_like(flux) + badmag
                mag[I] = sdss.nmgy_to_mag(flux[I])
                if len(extrabands):
                    mag = np.append(mag, np.zeros(len(extrabands)) + badmag)
                bright = Mags(order=bb, **dict(zip(bb, mag)))
            return bright

        def comp2bright(flux, Ldev, Lexp):
            dflux = flux * Ldev
            eflux = flux * Lexp
            dbright = nmgy2bright(dflux)
            ebright = nmgy2bright(eflux)
            return dbright, ebright

        flux2bright = nmgy2bright
        starflux = objs.psfflux
        compflux = objs.cmodelflux
        devflux = objs.devflux
        expflux = objs.expflux

    sources = []
    nstars, ndev, nexp, ncomp = 0, 0, 0, 0
    isources = []

    ptsrcclass = classmap.get(PointSource, PointSource)

    for i in range(len(objs)):
        if Lstar[i]:
            pos = RaDecPos(objs.ra[i], objs.dec[i])
            flux = starflux[i, :]
            bright = flux2bright(flux)
            # This should work, I just don't feel like testing it now...
            # if brightPointSourceThreshold:
            #   ps = SdssPointSource(pos, bright, thresh=brightPointSourceThreshold)
            # else:
            #   ps = PointSource(pos, bright)
            sources.append(ptsrcclass(pos, bright))
            nstars += 1
            isources.append(i)
            continue

        hasdev = (Ldev[i] > 0)
        hasexp = (Lexp[i] > 0)
        iscomp = (hasdev and hasexp)
        pos = RaDecPos(objs.ra[i], objs.dec[i])
        if iscomp:
            flux = compflux[i, :]
        elif hasdev:
            flux = devflux[i, :]
        elif hasexp:
            flux = expflux[i, :]
        else:
            print(
                'Skipping object with Lstar = %g, Ldev = %g, Lexp = %g (fracdev=%g)'
                % (Lstar[i], Ldev[i], Lexp[i], fracdev[i]))
            continue

        isources.append(i)
        if iscomp:
            if fixedComposites:
                bright = flux2bright(flux)
                fdev = (Ldev[i] / (Ldev[i] + Lexp[i]))
            else:
                dbright, ebright = comp2bright(flux, Ldev[i], Lexp[i])
        else:
            bright = flux2bright(flux)

        if hasdev:
            re = objs.theta_dev[i, bandnum]
            ab = objs.ab_dev[i, bandnum]
            phi = objs.phi_dev_deg[i, bandnum]
            dshape = ellipse(re, ab, phi)
        if hasexp:
            re = objs.theta_exp[i, bandnum]
            ab = objs.ab_exp[i, bandnum]
            phi = objs.phi_exp_deg[i, bandnum]
            eshape = ellipse(re, ab, phi)

        if iscomp:
            if fixedComposites:
                gal = FixedCompositeGalaxy(pos, bright, fdev, eshape, dshape)
            else:
                gal = CompositeGalaxy(pos, ebright, eshape, dbright, dshape)
            ncomp += 1
        elif hasdev:
            gal = DevGalaxy(pos, bright, dshape)
            ndev += 1
        elif hasexp:
            gal = ExpGalaxy(pos, bright, eshape)
            nexp += 1
        sources.append(gal)

    print(
        'Created',
        ndev,
        'deV,',
        nexp,
        'exp,',
        ncomp,
        'composite',
    )
    print('(total %i) galaxies and %i stars' % (ndev + nexp + ncomp, nstars))

    if not (getobjs or getobjinds or getsourceobjs):
        return sources

    if nstars + ndev + nexp + ncomp < len(objs):
        objs = objs[np.array(isources)]

    rtn = [sources]
    if getobjs:
        rtn.append(allobjs)
    if getobjinds:
        rtn.append(objs.index if len(objs) else np.array([]))
    if getsourceobjs:
        rtn.append(objs)
    return rtn
예제 #11
0
파일: sdss.py 프로젝트: lyczek/tractor
def _get_tractor_image_dr8(run, camcol, field, bandname, sdss=None,
                          roi=None, psf='kl-gm', roiradecsize=None,
                          roiradecbox=None,
                          savepsfimg=None, curl=False,
                          nanomaggies=False,
                          zrange=[-3,10],
                          invvarIgnoresSourceFlux=False,
                          invvarAtCenter=False,
                          invvarAtCenterImage=False,
                          imargs={}):
    # retry_retrieve=True,
    '''
    Creates a tractor.Image given an SDSS field identifier.

    If not None, roi = (x0, x1, y0, y1) defines a region-of-interest
    in the image, in zero-indexed pixel coordinates.  x1,y1 are
    NON-inclusive; roi=(0,100,0,100) will yield a 100 x 100 image.

    psf can be:
      "dg" for double-Gaussian
      "kl-gm" for SDSS KL-decomposition approximated as a Gaussian mixture

      "bright-*", "*" one of the above PSFs, with special handling at
      the bright end.

    "roiradecsize" = (ra, dec, half-size in pixels) indicates that you
    want to grab a ROI around the given RA,Dec.

    "roiradecbox" = (ra0, ra1, dec0, dec1) indicates that you
    want to grab a ROI containing the given RA,Dec ranges.

    "invvarAtCentr" -- get a scalar constant inverse-variance

    "invvarAtCenterImage" -- get a scalar constant inverse-variance
    but still make an image out of it.

    Returns: (tractor.Image, dict)

    dict contains useful details like:
      'sky'
      'skysig'
    '''
    from astrometry.sdss import band_index

    origpsf = psf
    if psf.startswith('bright-'):
        psf = psf[7:]
        brightpsf = True
        print('Setting bright PSF handling')
    else:
        brightpsf = False

    valid_psf = ['dg', 'kl-gm', 'kl-pix']
    if psf not in valid_psf:
        raise RuntimeError('PSF must be in ' + str(valid_psf))

    if sdss is None:
        from astrometry.sdss import DR8
        sdss = DR8(curl=curl)

    bandnum = band_index(bandname)

    for ft in ['psField', 'fpM']:
        fn = sdss.retrieve(ft, run, camcol, field, bandname)
    fn = sdss.retrieve('frame', run, camcol, field, bandname)

    # http://data.sdss3.org/datamodel/files/BOSS_PHOTOOBJ/frames/RERUN/RUN/CAMCOL/frame.html
    frame = sdss.readFrame(run, camcol, field, bandname, filename=fn)

    #image = frame.getImage().astype(np.float32)
    #(H,W) = image.shape

    H,W = frame.getImageShape()
    
    info = dict()
    hdr = frame.getHeader()
    tai = hdr.get('TAI')
    stripe = hdr.get('STRIPE')
    strip = hdr.get('STRIP')
    obj = hdr.get('OBJECT')
    info.update(tai=tai, stripe=stripe, strip=strip, object=obj, hdr=hdr)

    astrans = frame.getAsTrans()
    wcs = SdssWcs(astrans)
    #print('Created SDSS Wcs:', wcs)
    #print('(x,y) = 1,1 -> RA,Dec', wcs.pixelToPosition(1,1))

    X = interpret_roi(wcs, (H,W), roi=roi, roiradecsize=roiradecsize,
                               roiradecbox=roiradecbox)
    if X is None:
        return None,None
    roi,hasroi = X
    info.update(roi=roi)
    x0,x1,y0,y1 = roi

    # Mysterious half-pixel shift.  asTrans pixel coordinates?
    wcs.setX0Y0(x0 + 0.5, y0 + 0.5)

    if nanomaggies:
        photocal = LinearPhotoCal(1., band=bandname)
    else:
        photocal = SdssNanomaggiesPhotoCal(bandname)

    sky = 0.
    skyobj = ConstantSky(sky)

    calibvec = frame.getCalibVec()

    invvarAtCenter = invvarAtCenter or invvarAtCenterImage

    psfield = sdss.readPsField(run, camcol, field)
    iva = dict(ignoreSourceFlux=invvarIgnoresSourceFlux)
    if invvarAtCenter:
        if hasroi:
            iva.update(constantSkyAt=((x0+x1)/2., (y0+y1)/2.))
        else:
            iva.update(constantSkyAt=(W/2., H/2.))
    invvar = frame.getInvvar(psfield, bandnum, **iva)
    invvar = invvar.astype(np.float32)
    if not invvarAtCenter:
        assert(invvar.shape == (H,W))

    # Could get this from photoField instead
    # http://data.sdss3.org/datamodel/files/BOSS_PHOTOOBJ/RERUN/RUN/photoField.html
    gain = psfield.getGain(bandnum)
    darkvar = psfield.getDarkVariance(bandnum)

    meansky = np.mean(frame.sky)
    meancalib = np.mean(calibvec)
    skysig = sqrt((meansky / gain) + darkvar) * meancalib

    info.update(sky=sky, skysig=skysig)
    zr = np.array(zrange)*skysig + sky
    info.update(zr=zr)

    # http://data.sdss3.org/datamodel/files/PHOTO_REDUX/RERUN/RUN/objcs/CAMCOL/fpM.html
    fpM = sdss.readFpM(run, camcol, field, bandname)

    if not hasroi:
        image = frame.getImage()

    else:
        roislice = (slice(y0,y1), slice(x0,x1))
        image = frame.getImageSlice(roislice).astype(np.float32)
        if invvarAtCenterImage:
            invvar = invvar + np.zeros(image.shape, np.float32)
        elif invvarAtCenter:
            pass
        else:
            invvar = invvar[roislice].copy()
        H,W = image.shape
            
    if (not invvarAtCenter) or invvarAtCenterImage:
        for plane in [ 'INTERP', 'SATUR', 'CR', 'GHOST' ]:
            fpM.setMaskedPixels(plane, invvar, 0, roi=roi)

    dgpsf = psfield.getDoubleGaussian(bandnum, normalize=True)
    info.update(dgpsf=dgpsf)
            
    if psf == 'kl-pix':
        # Pixelized KL-PSF
        klpsf = psfield.getPsfAtPoints(bandnum, x0+W/2, y0+H/2)
        # Trim symmetric zeros
        sh,sw = klpsf.shape
        while True:
            if (np.all(klpsf[0,:] == 0.) and
                np.all(klpsf[:,0] == 0.) and
                np.all(klpsf[-1,:] == 0.) and
                np.all(klpsf[:,-1] == 0.)):
                klpsf = klpsf[1:-1, 1:-1]
            else:
                break

        mypsf = PixelizedPSF(klpsf)
        
    elif psf == 'kl-gm':
        from emfit import em_fit_2d
        from fitpsf import em_init_params
        
        # Create Gaussian mixture model PSF approximation.
        klpsf = psfield.getPsfAtPoints(bandnum, x0+W/2, y0+H/2)
        S = klpsf.shape[0]
        # number of Gaussian components
        K = 3
        w,mu,sig = em_init_params(K, None, None, None)
        II = klpsf.copy()
        II /= II.sum()
        # HIDEOUS HACK
        II = np.maximum(II, 0)
        #print('Multi-Gaussian PSF fit...')
        xm,ym = -(S/2), -(S/2)
        if savepsfimg is not None:
            plt.clf()
            plt.imshow(II, interpolation='nearest', origin='lower')
            plt.title('PSF image to fit with EM')
            plt.savefig(savepsfimg)
        res = em_fit_2d(II, xm, ym, w, mu, sig)
        #print('em_fit_2d result:', res)
        if res == 0:
            # print('w,mu,sig', w,mu,sig)
            mypsf = GaussianMixturePSF(w, mu, sig)
            mypsf.computeRadius()
        else:
            # Failed!  Return 'dg' model instead?
            print('PSF model fit', psf, 'failed!  Returning DG model instead')
            psf = 'dg'
    if psf == 'dg':
        print('Creating double-Gaussian PSF approximation')
        (a,s1, b,s2) = dgpsf
        mypsf = NCircularGaussianPSF([s1, s2], [a, b])

    if brightpsf:
        print('Wrapping PSF in SdssBrightPSF')
        (a1,s1, a2,s2, a3,sigmap,beta) = psfield.getPowerLaw(bandnum)
        mypsf = SdssBrightPSF(mypsf, a1,s1,a2,s2,a3,sigmap,beta)
        print('PSF:', mypsf)

    timg = Image(data=image, invvar=invvar, psf=mypsf, wcs=wcs,
                 sky=skyobj, photocal=photocal,
                 name=('SDSS (r/c/f/b=%i/%i/%i/%s)' %
                       (run, camcol, field, bandname)),
                 time=TAITime(tai),
                 **imargs)
    timg.zr = zr
    return timg,info
예제 #12
0
파일: sdss.py 프로젝트: lyczek/tractor
def get_tractor_image(run, camcol, field, bandname, 
                      sdssobj=None, release='DR7',
                      retrieve=True, curl=False,
                      psf='kl-gm', useMags=False,
                      roi=None,
                      roiradecsize=None,
                      roiradecbox=None,
                      nanomaggies=False,
                      savepsfimg=None, zrange=[-3,10]):
    '''
    Creates a tractor.Image given an SDSS field identifier.

    If not None, roi = (x0, x1, y0, y1) defines a region-of-interest
    in the image, in zero-indexed pixel coordinates.  x1,y1 are
    NON-inclusive; roi=(0,100,0,100) will yield a 100 x 100 image.
    
    psf can be:
      "dg" for double-Gaussian
      "kl-gm" for SDSS KL-decomposition approximated as a Gaussian mixture

    "roiradecsize" = (ra, dec, half-size in pixels) indicates that you
    want to grab a ROI around the given RA,Dec.

    Returns:
      (tractor.Image, dict)

    dict contains useful details like:
      'sky'
      'skysig'
    '''
    from astrometry.sdss import DR7, band_index

    if sdssobj is None:
        # Ugly
        if release != 'DR7':
            raise RuntimeError('We only support DR7 currently')
        sdss = DR7(curl=curl)
    else:
        sdss = sdssobj

    valid_psf = ['dg', 'kl-gm']
    if psf not in valid_psf:
        raise RuntimeError('PSF must be in ' + str(valid_psf))
    # FIXME
    rerun = 0

    bandnum = band_index(bandname)

    _check_sdss_files(sdss, run, camcol, field, bandname,
                      ['fpC', 'tsField', 'psField', 'fpM'],
                      retrieve=retrieve)
    fpC = sdss.readFpC(run, camcol, field, bandname)
    hdr = fpC.getHeader()
    fpC = fpC.getImage()
    fpC = fpC.astype(np.float32) - sdss.softbias
    image = fpC
    (H,W) = image.shape

    info = dict()
    tai = hdr.get('TAI')
    stripe = hdr.get('STRIPE')
    strip = hdr.get('STRIP')
    obj = hdr.get('OBJECT')
    info.update(tai=tai, stripe=stripe, strip=strip, object=obj, hdr=hdr)

    tsf = sdss.readTsField(run, camcol, field, rerun)
    astrans = tsf.getAsTrans(bandnum)
    wcs = SdssWcs(astrans)
    #print('Created SDSS Wcs:', wcs)

    X = interpret_roi(wcs, (H,W), roi=roi, roiradecsize=roiradecsize,
                      roiradecbox=roiradecbox)
    if X is None:
        return None,None
    roi,hasroi = X
    info.update(roi=roi)
    x0,x1,y0,y1 = roi
        
    # Mysterious half-pixel shift.  asTrans pixel coordinates?
    wcs.setX0Y0(x0 + 0.5, y0 + 0.5)

    if nanomaggies:
        zp = tsf.get_zeropoint(bandnum)
        photocal = LinearPhotoCal(NanoMaggies.zeropointToScale(zp),
                                  band=bandname)
    elif useMags:
        photocal = SdssMagsPhotoCal(tsf, bandname)
    else:
        photocal = SdssFluxPhotoCal()

    psfield = sdss.readPsField(run, camcol, field)
    sky = psfield.getSky(bandnum)
    skysig = sqrt(sky)
    skyobj = ConstantSky(sky)
    zr = sky + np.array(zrange) * skysig
    info.update(sky=sky, skysig=skysig, zr=zr)

    fpM = sdss.readFpM(run, camcol, field, bandname)
    gain = psfield.getGain(bandnum)
    darkvar = psfield.getDarkVariance(bandnum)
    skyerr = psfield.getSkyErr(bandnum)
    invvar = sdss.getInvvar(fpC, fpM, gain, darkvar, sky, skyerr)

    dgpsf = psfield.getDoubleGaussian(bandnum, normalize=True)
    info.update(dgpsf=dgpsf)
    
    if roi is not None:
        roislice = (slice(y0,y1), slice(x0,x1))
        image = image[roislice].copy()
        invvar = invvar[roislice].copy()

    if psf == 'kl-gm':
        from emfit import em_fit_2d
        from fitpsf import em_init_params

        # Create Gaussian mixture model PSF approximation.
        H,W = image.shape
        klpsf = psfield.getPsfAtPoints(bandnum, x0+W/2, y0+H/2)
        S = klpsf.shape[0]
        # number of Gaussian components
        K = 3
        w,mu,sig = em_init_params(K, None, None, None)
        II = klpsf.copy()
        II /= II.sum()
        # HIDEOUS HACK
        II = np.maximum(II, 0)
        #print('Multi-Gaussian PSF fit...')
        xm,ym = -(S/2), -(S/2)
        if savepsfimg is not None:
            plt.clf()
            plt.imshow(II, interpolation='nearest', origin='lower')
            plt.title('PSF image to fit with EM')
            plt.savefig(savepsfimg)
        res = em_fit_2d(II, xm, ym, w, mu, sig)
        print('em_fit_2d result:', res)
        if res == 0:
            # print('w,mu,sig', w,mu,sig)
            mypsf = GaussianMixturePSF(w, mu, sig)
            mypsf.computeRadius()
        else:
            # Failed!  Return 'dg' model instead?
            print('PSF model fit', psf, 'failed!  Returning DG model instead')
            psf = 'dg'
    if psf == 'dg':
        print('Creating double-Gaussian PSF approximation')
        (a,s1, b,s2) = dgpsf
        mypsf = NCircularGaussianPSF([s1, s2], [a, b])
        
    timg = Image(data=image, invvar=invvar, psf=mypsf, wcs=wcs,
                 sky=skyobj, photocal=photocal,
                 name=('SDSS (r/c/f/b=%i/%i/%i/%s)' %
                       (run, camcol, field, bandname)))
    timg.zr = zr
    return timg,info
예제 #13
0
파일: sdss.py 프로젝트: lyczek/tractor
def _get_sources(run, camcol, field, bandname='r', sdss=None, release='DR7',
                 objs=None,
                 retrieve=True, curl=False, roi=None,
                 radecroi=None,
                 radecrad=None,
                 bands=None,
                 badmag=25, nanomaggies=False,
                 getobjs=False, getsourceobjs=False, getobjinds=False,
                 extrabands=None,
                 fixedComposites=False,
                 forcePointSources=False,
                 useObjcType=False,
                 objCuts=True,
                 classmap={},
                 ellipse=GalaxyShape,
                 cutToPrimary=False):
    '''
    If set,

    radecrad = (ra,dec,rad)

    returns sources within "rad" degrees of the given RA,Dec (in degrees)
    center.

    WARNING, this method alters the "objs" argument, if given.
    Consider calling objs.copy() before calling.

    -"bandname" is the SDSS band used to cut on position, select
     star/gal/exp/dev, and set galaxy shapes.

    -"bands" are the bands to include in the returned Source objects;
     they will be initialized from the SDSS bands.

    -"extrabands" are also included in the returned Source objects;
     they will be initialized to the SDSS flux for either the first of
     "bands", if given, or "bandname".
    '''
    from astrometry.sdss import (DR7, DR8, DR9, band_names, band_index,
                                 photo_flags1_map)
    
    #   brightPointSourceThreshold=0.):

    if sdss is None:
        dr = dict(DR7=DR7, DR8=DR8, DR9=DR9)[release]
        sdss = dr(curl=curl)
    drnum = sdss.getDRNumber()
    isdr7 = (drnum == 7)
    
    if bands is None:
        bands = band_names()
    bandnum = band_index(bandname)

    bandnums = np.array([band_index(b) for b in bands])
    bandnames = bands

    if extrabands is None:
        extrabands = []
    
    if objs is None:
        from astrometry.util.fits import fits_table
        if isdr7:
            # FIXME
            rerun = 0
            _check_sdss_files(sdss, run, camcol, field, bandnum,
                              ['tsObj', 'tsField'],
                              retrieve=retrieve, tryopen=True)
            tsf = sdss.readTsField(run, camcol, field, rerun)
            
            objfn = sdss.getPath('tsObj', run, camcol, field,
                                 bandname, rerun=rerun)
        else:
            _check_sdss_files(sdss, run, camcol, field, bandnum, ['photoObj'],
                              tryopen=True, retrieve=retrieve)
            objfn = sdss.getPath('photoObj', run, camcol, field)
            
        objs = fits_table(objfn)
        if objs is None:
            print('No sources in SDSS file', objfn)
            return []

    objs.index = np.arange(len(objs))
    if getobjs:
        allobjs = objs.copy()
        
    if roi is not None:
        x0,x1,y0,y1 = roi
        # FIXME -- we keep only the sources whose centers are within
        # the ROI box.  Should instead do some ellipse-overlaps
        # geometry.
        x = objs.colc[:,bandnum]
        y = objs.rowc[:,bandnum]
        objs.cut((x >= x0) * (x < x1) * (y >= y0) * (y < y1))

    if radecroi is not None:
        r0,r1,d0,d1 = radecroi
        objs.cut((objs.ra >= r0) * (objs.ra <= r1) *
                 (objs.dec >= d0) * (objs.dec <= d1))

    if radecrad is not None:
        from astrometry.libkd.spherematch import match_radec
        (ra,dec,rad) = radecrad
        I,J,d = match_radec(ra, dec, objs.ra, objs.dec, rad)
        objs.cut(J)
        del I
        del d
        
    if objCuts:
        # Only deblended children;
        # No BRIGHT sources
        bright = photo_flags1_map.get('BRIGHT')
        objs.cut((objs.nchild == 0) * ((objs.objc_flags & bright) == 0))

    if cutToPrimary:
        objs.cut((objs.resolve_status & 256) > 0)
        
    if isdr7:
        objs.rename('phi_dev', 'phi_dev_deg')
        objs.rename('phi_exp', 'phi_exp_deg')
        objs.rename('r_dev', 'theta_dev')
        objs.rename('r_exp', 'theta_exp')
        
    # SDSS and Tractor have different opinions on which way this rotation goes
    objs.phi_dev_deg *= -1.
    objs.phi_exp_deg *= -1.

    # MAGIC -- minimum size of galaxy.
    objs.theta_dev = np.maximum(objs.theta_dev, 1./30.)
    objs.theta_exp = np.maximum(objs.theta_exp, 1./30.)

    if forcePointSources:
        Lstar = np.ones(len(objs), float)
        Lgal = np.zeros(len(objs), float)
        Ldev = Lexp = Lgal
    else:
        if useObjcType:
            objs.cut(np.logical_or(objs.objc_type == 6,
                                   objs.objc_type == 3))
            Lstar = (objs.objc_type == 6)
            Lgal = (objs.objc_type == 3)
        else:
            Lstar = (objs.prob_psf[:,bandnum] == 1) * 1.0
            Lgal  = (objs.prob_psf[:,bandnum] == 0)
        if isdr7:
            fracdev = objs.fracpsf[:,bandnum]
        else:
            fracdev = objs.fracdev[:,bandnum]
        Ldev = Lgal * fracdev
        Lexp = Lgal * (1. - fracdev)

    if isdr7:
        if nanomaggies:
            raise RuntimeError('Nanomaggies not supported for DR7 (yet)')
        def lup2bright(lups):
            counts = [tsf.luptitude_to_counts(lup,j)
                      for j,lup in enumerate(lups)]
            counts = np.array(counts)
            bright = _getBrightness(counts, tsf, bandnames, extrabands)
            return bright
        flux2bright = lup2bright
        starflux = objs.psfcounts
        compflux = objs.counts_model
        devflux = objs.counts_dev
        expflux = objs.counts_exp
        def comp2bright(lups, Ldev, Lexp):
            counts = [tsf.luptitude_to_counts(lup,j)
                      for j,lup in enumerate(lups)]
            counts = np.array(counts)
            dcounts = counts * Ldev
            ecounts = counts * Lexp
            dbright = _getBrightness(dcounts, tsf, bands, extrabands)
            ebright = _getBrightness(ecounts, tsf, bands, extrabands)
            return dbright, ebright
    else:
        def nmgy2bright(flux):
            if len(bandnums):
                flux = flux[bandnums]
            else:
                flux = flux[np.array([bandnum])]
            bb = bandnames + extrabands
            if nanomaggies:
                if len(extrabands):
                    if len(bandnums) == 0:
                        # Only "extrabands", no SDSS bands.
                        flux = np.zeros(len(extrabands)) + flux[0]
                    else:
                        flux = np.append(flux, np.zeros(len(extrabands)))
                bright = NanoMaggies(order=bb, **dict(zip(bb, flux)))
            else:
                I = (flux > 0)
                mag = np.zeros_like(flux) + badmag
                mag[I] = sdss.nmgy_to_mag(flux[I])
                if len(extrabands):
                    mag = np.append(mag, np.zeros(len(extrabands)) + badmag)
                bright = Mags(order=bb, **dict(zip(bb,mag)))
            return bright
        def comp2bright(flux, Ldev, Lexp):
            dflux = flux * Ldev
            eflux = flux * Lexp
            dbright = nmgy2bright(dflux)
            ebright = nmgy2bright(eflux)
            return dbright, ebright
        
        flux2bright = nmgy2bright
        starflux = objs.psfflux
        compflux = objs.cmodelflux
        devflux = objs.devflux
        expflux = objs.expflux
        
    sources = []
    nstars, ndev, nexp, ncomp = 0, 0, 0, 0
    isources = []

    ptsrcclass = classmap.get(PointSource, PointSource)

    for i in range(len(objs)):
        if Lstar[i]:
            pos = RaDecPos(objs.ra[i], objs.dec[i])
            flux = starflux[i,:]
            bright = flux2bright(flux)
            # This should work, I just don't feel like testing it now...
            # if brightPointSourceThreshold:
            #   ps = SdssPointSource(pos, bright, thresh=brightPointSourceThreshold)
            # else:
            #   ps = PointSource(pos, bright)
            sources.append(ptsrcclass(pos, bright))
            nstars += 1
            isources.append(i)
            continue

        hasdev = (Ldev[i] > 0)
        hasexp = (Lexp[i] > 0)
        iscomp = (hasdev and hasexp)
        pos = RaDecPos(objs.ra[i], objs.dec[i])
        if iscomp:
            flux = compflux[i,:]
        elif hasdev:
            flux = devflux[i,:]
        elif hasexp:
            flux = expflux[i,:]
        else:
            print('Skipping object with Lstar = %g, Ldev = %g, Lexp = %g (fracdev=%g)'
                  % (Lstar[i], Ldev[i], Lexp[i], fracdev[i]))
            continue

        isources.append(i)
        if iscomp:
            if fixedComposites:
                bright = flux2bright(flux)
                fdev = (Ldev[i] / (Ldev[i] + Lexp[i]))
            else:
                dbright,ebright = comp2bright(flux, Ldev[i], Lexp[i])
        else:
            bright = flux2bright(flux)

        if hasdev:
            re  = objs.theta_dev  [i,bandnum]
            ab  = objs.ab_dev     [i,bandnum]
            phi = objs.phi_dev_deg[i,bandnum]
            dshape = ellipse(re, ab, phi)
        if hasexp:
            re  = objs.theta_exp  [i,bandnum]
            ab  = objs.ab_exp     [i,bandnum]
            phi = objs.phi_exp_deg[i,bandnum]
            eshape = ellipse(re, ab, phi)

        if iscomp:
            if fixedComposites:
                gal = FixedCompositeGalaxy(pos, bright, fdev, eshape, dshape)
            else:
                gal = CompositeGalaxy(pos, ebright, eshape, dbright, dshape)
            ncomp += 1
        elif hasdev:
            gal = DevGalaxy(pos, bright, dshape)
            ndev += 1
        elif hasexp:
            gal = ExpGalaxy(pos, bright, eshape)
            nexp += 1
        sources.append(gal)

    print('Created', ndev, 'deV,', nexp, 'exp,', ncomp, 'composite',)
    print('(total %i) galaxies and %i stars' % (ndev+nexp+ncomp, nstars))
    
    if not (getobjs or getobjinds or getsourceobjs):
        return sources

    if nstars + ndev + nexp + ncomp < len(objs):
        objs = objs[np.array(isources)]
    
    rtn = [sources]
    if getobjs:
        rtn.append(allobjs)
    if getobjinds:
        rtn.append(objs.index if len(objs) else np.array([]))
    if getsourceobjs:
        rtn.append(objs)
    return rtn